The invention relates to a microscope control unit comprising manually operable, cylindrical operating elements for x/y-adjustment of a mechanical stage and alternatively for the z-adjustment of the focus setting of a microscope.
It is well-known to attach, to the underside of mechanical stages, manually operable operating elements that separately transmit, e.g., by means of cable controls or gearwheels, the rotation of cylindrical barrels to the stage surfaces to be displaced. The frictional forces to be overcome in this case give the operator a feeling for the stage movement. At least one of the moved stage surfaces usually carries the operating elements along. The operator's hand must follow on the working surface. The operating elements must be attached to different sides of the microscope stage for left-handers or right-handers. The possibility of retrofitting is associated with a higher design effort. Sufficient clearance for the positioning of the hand rest and arm rest for the operator must be kept free in the area of the microscope stage surface.
For motor-driven stage adjustments, the rotation of the operating elements attached to the mechanical stage can be converted to electrical counter and control pulses. The operating elements can be provided with adjustable friction torques to simulate the feel of a mechanical coupling between operating element and stage movement for the operator.
For motor-driven stage adjustments, it is also known to accommodate the manually operable operating elements in separate housings and to transmit the control signals for the stage adjustment through electrical lines and plug connections attached to the mechanical stage. To this end, trackball and joystick control units are well-known in particular. Both right-handers and left-handers can operate these control units since they can be freely positioned on the work stage. The disadvantage is that the mechanical stage cannot be reliably set to a precise position because of the ease of movement of the operating elements. In the joystick controller, the operating lever automatically jumps back to the zero position after the operator lets go of a setting that was achieved. To make a correction or choose a new setting, the operator must again make out the zero position by touch with his/her finger. An undesired stage adjustment can be triggered by accidently nudging the operating lever.
For manual, mechanically-operated stage adjustments when using control units with interconnected coarse and fine adjustments of the operating elements, a rapid stage adjustment over large adjustment paths and a precise positioning in a small observation area are usually accomplished through different gear ratios. The respective operating elements are usually arranged coaxially aligned with one another with different roll diameters so that the operator can comfortably change his/her grip from coarse to fine adjustment or vice versa.
For electronic transmission of the motion of the operating elements to servomotors, it is possible to adjust different translations of the counter and control pulses to the engine speeds by means of electrical switches and software programming.
In addition to operating elements for the x/y mechanical-stage adjustment, microscopes also have operating elements for the z-adjustment of the mechanical stage or of the body tubes for the focus setting of the lens. These are usually attached to the microscope stand and therefore require a laborious change of grip from the microscope stage to the microscope stand.
The housings of the already described trackball and joystick controllers therefore also have additional control wheels for the z-drive in handy proximity to the x/y operating elements. The operator must therefore prepare himself/herself for different reactions to the different movements for adjusting a control level or for the rolling of a ball and the rotating of a wheel. The operator is therefore required to exercise additional concentration when changing grip from one operating element to another.